Continuity Test voltage 2.9 volts or 0.44 volts, LRC meter with ext. power supply

[Billy Mayo]

My Fluke meter 87 Continuity checker mode test voltage is 2.9 volts
My Fluke 70 III Continuity Checker mode test voltage is 2.5 volts
My Craftsman meter Continuity Checker mode test voltage is at 0.443 volts

When a Continuity Test voltage is at 2.9 volts , what advantage does it have , over my Craftmans Continuity test voltage which is at 0.443?

Why would u want a Continuity test voltage at 2.9 volts? or why would u want a continuity test voltage at 0.443? what do they do differently when measuring Continuity on a circuit board?


An LCR meter when measuring Capacitors , test voltage is zero volts in some settings and others settings its 3 volts

Can I hook up an external power supply and set the power supply to the voltage rating of the capacitor and use the LCR meter in parallel to measure the capacitance of the capacitor at the voltage rating using WITH an ext. power supply? or will this damage the LCR meter>?

 

[large_ghostman]

My Fluke meter 87 Continuity checker mode test voltage is 2.9 volts
My Fluke 70 III Continuity Checker mode test voltage is 2.5 volts
My Craftsman meter Continuity Checker mode test voltage is at 0.443 volts

When a Continuity Test voltage is at 2.9 volts , what advantage does it have , over my Craftmans Continuity test voltage which is at 0.443?

Why would u want a Continuity test voltage at 2.9 volts? or why would u want a continuity test voltage at 0.443? what do they do differently when measuring Continuity on a circuit board?


An LCR meter when measuring Capacitors , test voltage is zero volts in some settings and others settings its 3 volts

Can I hook up an external power supply and set the power supply to the voltage rating of the capacitor and use the LCR meter in parallel to measure the capacitance of the capacitor at the voltage rating using WITH an ext. power supply? or will this damage the LCR meter>?

<0.6V when I want to test circuits without turning gates etc on,

>2V When I want to test continuity in cable runs over a few meters (think about why that might be, Google Ohms law for a clue, if you dont understand Ohms law, cut and paste into google translate, see if it has a English to muppet translation)

next bit answered by <0.6V question


LCR meter
What LCR meter? Why are they letting you play with technical equipment?

Depends on the meter, I have 2
One says no voltage on caps or else, one says no voltage on caps >12V, as it discharges the cap.
What would you hope to achieve by Volting the cap to its rating? Do you know what a LCR meter does?? or did the shiny buttons make you play with it?
I cant see a valid reason you would want to charge the cap up???????? if it was needed then the meter would do it. Put the meter down gently on the bench and walk away, you will break it!

 

[Billy Mayo]

One continuity meter has a test voltage of 0.443V. The other continuity tester has a test voltage of 2.9V.
The Fluke 87 continuity test outputs 2.9 volts, in continuity mode, this WILL turn on diodes, logic Gates Inputs and outputs, turn on transistors, turns on semiconductors

Craftmans meter continuity test outputs 0.4 volts, in continuity mode, this WON'T and Will not turn on diodes, logic Gates Inputs and outputs, turn on transistors, turns on semiconductors

OHMS mode test voltage is 0.2 volts, so you can't turn on semiconductors or Logic Gates inputs and outputs

I don't get why FLUKE meters want 2.9 volts for continuity test? for what reason?

It can turn on semiconductors and Logic gates inputs and outputs, why would u want 2.9 volts in continuity testing mode?

I don't get it

 

[4pyros]

For testing semiconductors

 

[JoeJester]

Your Flukes have technical manuals. I suggest you read them.
Your LCR has a manual also. Enjoy reading.

You have put forth yourself as a technician. Start reading.

Can I hook up an external power supply and set the power supply to the voltage rating of the capacitor and use the LCR meter in parallel to measure the capacitance of the capacitor at the voltage rating using WITH an ext. power supply? or will this damage the LCR meter>?

Can you hook yourself up to a 45000 volt line and ground without damaging yourself?

 

[JoeJester]

I cant see a valid reason you would want to charge the cap up????????

LG, How do you test capacitor leakage in a 20 kV 10 uF capacitor?

 

[JimB]

I cant see a valid reason you would want to charge the cap up????????

So LG:
How would you test an electrolytic capacitor?
Does the capacitance vary with polarising voltage?

JimB

 

[Billy Mayo]

For testing semiconductors

It can turn on semiconductors and Logic gates inputs and outputs, why would u want 2.9 volts in continuity testing mode?

THAT IS BAD not GOOD in continuity tester mode

Why is it at 2.9 volts , what semiconductors need a forward bias at 2.9 volts?

 

[4pyros]

It can turn on semiconductors and Logic gates inputs and outputs, why would u want 2.9 volts in continuity testing mode?

THAT IS BAD not GOOD in continuity tester mode

Why is it at 2.9 volts , what semiconductors need a forward bias at 2.9 volts?

1st off neither of your Fluke meters have a "continuity tester mode"!!!!!!
Read your manuals to understand your equipment!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

[Billy Mayo]

1st

off neither of your Fluke meters have a "continuity tester mode"!!!!!!

Yes it does, it beeps

 

[JoeJester]

When does it beep?

 

[Billy Mayo]

put the probe together or when measuring continuity between traces or when something is very low resistance

I'm not sure why the test voltage for continuity is 2.9 volts , any reason why?

 

[JoeJester]

I'm sure the manual for the fluke did not express those words. I recommend you download those manuals and read them.

It's time for you to step up and do some research.

 

[large_ghostman]

LG, How do you test capacitor leakage in a 20 kV 10 uF capacitor?

I have been asked by moderation not to post in his threads, but I cant resist since you asked me.
I wouldnt test leakage with any of my LCR meters! In fact I couldnt test with my Meters as they wont tolerate a voltage already on a cap,
So I guess this gives me two choices, a quick method, charge the cap up to a known voltage (I would use 1/2 max voltage), leave a set time and with a very high impedance Volt meter, (cant remember what the bench meter is, but way above most hand helds) read off the voltage,
OR if I needed to do this alot I would bug dad to get electrometer.
I did actualy ask what LCR meter he was using, I think even the atlas discharges the cap first. So I see no reason he would charge a cap up to measure with a LCR meter, do you? have I missed something?

 

[Billy Mayo]

Can I charge up a capacitor using an ext. power supply to it's power rating and then measure the capacitance using an LCR meter? but how can i measure the leakage?

 

[kubeek]

Leakage is usually tested using a sensitive ampermeter. Simply put in series with the cap, short it at first and connect voltage source to allow the cap to charge and not blow the fuse on the meter, then remove the short on the meter and observe leakage current.

 

[large_ghostman]

So LG:
How would you test an electrolytic capacitor?
Does the capacitance vary with polarising voltage?

JimB

Not sure I understand this, I take polarizing voltage to mean AC, caps pass AC and block DC. Sorry to be thick but what exactly am I testing for? is a straight forward measure of capacitance?

Either way I still wouldnt charge the cap up for reading capacitance or ESR, most good LCR meters offer a choice of frequency to test with, I have 2 models and have used only 4, but non leave a charge on the cap before testing, I have to make sure no charge is present.

 

[kubeek]

Can I charge up a capacitor using an ext. power supply to it's power rating and then measure the capacitance using an LCR meter?

Consult your LCR´s manual, I highly doubt it would tolerate charged capacitors.

but how can i measure the leakage?

See my previous post.

 

[Billy Mayo]

THANKS for the info KUBEEK

This is what I have been waiting for it this kinda of test

For some reason the fluke meters at work blow fuses really easy in the ampermeter mode , current meter mode

When measuring the Leakage current like this, how do u know if it's leakage current or Not leakage current? what is not leakage current called i don't know the correct term

 

[kubeek]

its either charging/dischargin current + leakage current when the voltage across the cap is changing, or it is leakage when the voltage on the cap is stationary.